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DRC
2013-08-23 06:38:59 +00:00
parent 0fb3247f9a
commit ff3d754f29
8 changed files with 118 additions and 76 deletions
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28
java/doc/org/libjpegturbo/turbojpeg/TJCompressor.html
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@@ -469,7 +469,13 @@ public void <B>setSubsamp</B>(int&nbsp;newSubsamp)
throws java.lang.Exception</PRE>
<DL>
<DD>Set the level of chrominance subsampling for subsequent compress/encode
operations.
operations. When pixels are converted from RGB to YCbCr (see
<A HREF="../../../org/libjpegturbo/turbojpeg/TJ.html#CS_YCbCr"><CODE>TJ.CS_YCbCr</CODE></A>) or from CMYK to YCCK (see <A HREF="../../../org/libjpegturbo/turbojpeg/TJ.html#CS_YCCK"><CODE>TJ.CS_YCCK</CODE></A>) as part
of the JPEG compression process, some of the Cb and Cr (chrominance)
components can be discarded or averaged together to produce a smaller
image with little perceptible loss of image clarity (the human eye is more
sensitive to small changes in brightness than to small changes in color.)
This is called "chrominance subsampling".
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>newSubsamp</CODE> - the new level of chrominance subsampling (one of
@@ -609,14 +615,18 @@ public void <B>encodeYUV</B>(byte[]&nbsp;dstBuf,
instance and output a YUV planar image to the given destination buffer.
This method uses the accelerated color conversion routines in TurboJPEG's
underlying codec but does not execute any of the other steps in the JPEG
compression process. The Y, U, and V image planes are stored sequentially
into the destination buffer, and the size of each plane is determined by
the width and height of the source image, as well as the specified padding
and level of chrominance subsampling. If the chrominance components are
subsampled along the horizontal dimension, then the width of the luminance
plane is padded to the nearest multiple of 2 in the output image (same
goes for the height of the luminance plane, if the chrominance components
are subsampled along the vertical dimension.)
compression process. The Y, U (Cb), and V (Cr) image planes are stored
sequentially into the destination buffer, and the size of each plane is
determined by the width and height of the source image, as well as the
specified padding and level of chrominance subsampling. If the
chrominance components are subsampled along the horizontal dimension, then
the width of the luminance plane is padded to the nearest multiple of 2 in
the output image (same goes for the height of the luminance plane, if the
chrominance components are subsampled along the vertical dimension.)
<p>
NOTE: Technically, the JPEG format uses the YCbCr colorspace, but per the
convention of the digital video community, the TurboJPEG API uses "YUV" to
refer to an image format consisting of Y, Cb, and Cr image planes.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>dstBuf</CODE> - buffer that will receive the YUV planar image. Use